1. Field of the Invention
Exemplary embodiments of the present invention relate to a waste gas purification method, and more particularly, to a waste gas burning method of reducing CO and NOx by burning waste gases using a system for individually controlling CO and NOx.
2. Description of the Related Art
In general, waste gases, which are generated in an industrial process such as a semiconductor or LCD (Liquid Crystal Display) manufacturing process or a chemical process, have highly toxic, explosive, and corrosive properties. Accordingly, the waste gases are released as they are into the atmosphere to allow environmental pollution to be caused. Therefore, a purification process should be necessarily performed to reduce an amount of noxious components contained in the waste gases below the allowable concentration.
As a method of processing the waste gases generated in the semiconductor manufacturing process or the like, there is a burning method of decomposing, reacting, or burning a pyrophoric gas with a hydrogen radical or the like in a high temperature combustion chamber, a wet method of dissolving a water-soluble gas in water while the water-soluble gas passes through the water stored in a water reservoir, or an adsorption method of purifying a toxic gas, which is not pyrophoric and soluble, in such a manner that the toxic gas is adsorbed onto an adsorbent by physical or chemical adsorption during passing through the adsorbent.
The burning method utilizes a combustion apparatus to burn the waste gases. There is, however, a problem in that, in the combustion apparatus of the related art, the waste gases generated in the semiconductor manufacturing process and N2 gases used in a dry vacuum pump or the like are oxidized at a high temperature while being introduced into the combustion apparatus, thereby allowing large nitrogen oxides (NOx) to be rapidly generated.
Moreover, there is a problem that the waste gases are burned at a high temperature within the combustion chamber with the consequence that CO is introduced and generated due to incomplete combustion.
Furthermore, looking through combustion characteristics, a NOx concentration is increased by an increase in temperature within the combustion chamber as a CO concentration is decreased. Conversely, there is a problem in that a trade off relation occurs in which the CO concentration is increased as the NOx concentration is decreased.